By IANS
London : Microscopic marine plankton increase their carbon intake in response to increased concentrations of dissolved carbon dioxide and thus contribute to curbing the greenhouse effect on a global scale, a new study has found.
Researchers led by scientists at the Leibniz Institute of Marine Sciences in Kiel, Germany, have documented this biological mechanism in a natural plankton community for the first time, Sciencedaily.com reported.
In simulations of the future ocean, they measured an increased carbon dioxide (CO2) uptake of up to 39 percent. But the unexpected positive effect for the global climate system harbours at the same time considerable risks for the oceans and their ecosystems.
The study points to three major areas of concern: increased CO2 uptake by plankton will accelerate the rate of ocean acidification in deeper layers, lead to a decrease in oxygen concentrations in the deeper ocean, and will worsen the nutritional quality of plankton.
The last development can have consequences for entire food webs in the ocean.
The world’s oceans are by far the largest sink of CO2 on our planet. Until now, they have swallowed almost half of the CO2 emitted through the burning of fossil fuels.
But can the oceans continue to alleviate the steady rise in atmospheric CO2 in the future?
Current models for the development of the global climate system neither incorporate the reaction of marine organisms nor the processes that they influence.
“We need to learn a lot more about the biology of the oceans, because the organisms play a decisive role in the carbon cycle. How do they affect the chemical balance and what are their responses to the enormous environmental changes we are currently experiencing?” asks Ulf Riebesell, marine biologist and lead author of the study.